164475441520021 has 2 divisors, whose sum is σ = 164475441520022. Its totient is φ = 164475441520020.

The previous prime is 164475441519979. The next prime is 164475441520031. The reversal of 164475441520021 is 120025144574461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 163705909047121 + 769532472900 = 12794761^2 + 877230^2 .

It is a cyclic number.

It is not a de Polignac number, because 164475441520021 - 2¹¹ = 164475441517973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (164475441520031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82237720760010 + 82237720760011.

It is an arithmetic number, because the mean of its divisors is an integer number (82237720760011).

Almost surely, 2^{164475441520021} is an apocalyptic number.

It is an amenable number.

164475441520021 is a deficient number, since it is larger than the sum of its proper divisors (1).

164475441520021 is an equidigital number, since it uses as much as digits as its factorization.

164475441520021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1075200, while the sum is 46.

The spelling of 164475441520021 in words is "one hundred sixty-four trillion, four hundred seventy-five billion, four hundred forty-one million, five hundred twenty thousand, twenty-one".